Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Category
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Ferruginous Sandstone (Red Sandstone)
Arenite with Hematite/Limonite cement
Milky Quartz
Silicon Dioxide (SiO2)
Granite
Phaneritic Plutonic Felsic Rock
Turquoise
Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
Snowflake Obsidian
Volcanic glass with Spherulite inclusions (SiO2)
Orca Agate (Chalcedony)
Silicon Dioxide (SiO2) with inclusions
Ferruginous Sandstone
Sandstone (arenite) with Limonite/Goethite cement
Fossilized Coral
Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)
Gneiss
Gneissic Metamorphic Rock
Amethyst (Tumbled Chips)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Unakite
Epidotized Granite
Shale
Shale (comprised mostly of clay minerals and quartz)
Blue Quartz (Aventurine)
Silicon Dioxide (SiO2) with inclusions of crocidolite or dumortierite
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Ocean Jasper
Spherulitic Chalcedony (SiO2)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Dyed Pink Agate
Silicon Dioxide (SiO2) - variety Chalcedony
Gneiss (River Cobble)
Gneiss (Foliated Metamorphic Rock)
Schist
Mica Schist
Granite Thin Section
Granitic rock (Phaneritic texture)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)
Granite (with Quartz and Mica)
Phaneritic Felsic Igneous Rock
Stiped Slate Beach Pebble
Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Druzy or Crystalline variety)
Silicon Dioxide (SiO2)
Blue Kyanite
Kyanite (Al2SiO5)
Eudialyte in Matrix
Na15Ca6Fe3Zr3Si26O72(OH,Cl,H2O)3
Granite
Granite (Felsic Plutonic Rock)
Agate
Silicon dioxide (SiO2)
Gold Nugget Jewelry
Native Gold (Au)
Milky Quartz
Silicon Dioxide (SiO2)
Moss Agate and Druzy Quartz Carving
Cryptocrystalline Silica (SiO2) with impurities
Green Quartz (Prasiolite)
Silicon Dioxide (SiO2) with trace impurities
Banded Calcite (Green Onyx)
Calcium Carbonate (CaCO3)
Lapis Lazuli
Lapis Lazuli (Primary mineral: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Sandstone (Ferruginous/Banded)
Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)